The correct answer to this question is Nitrogen. It is the most abundant gas because it is essential to life on Earth. Nitrogen is found in all proteins and all living systems. The compounds of Nitrogen are also found in food, organic materials, poisons, and fertilizers.
While Nitrogen is essential to life, it can also be very harmful to the environment. Physician and chemist Daniel Rutherford discovered it in 1772. The atomic symbol for Nitrogen is N, and its atomic number is 7. As a gas, Nitrogen has no color and has no odor.